The Mössbauer effect and collective motions in glass-forming liquids and polymeric networks

Glass-forming liquids, synthetic polymers and biopolymers share essential properties. Dynamic processes in these complex systems are characterized by cooperative motions with wide distributions of time scales, which manifest themselves in broad quasielastic lines in the Mössbauer spectrum. In this article, the application of the Mössbauer effect to the study of structural dynamics in complex systems is discussed.     

Conjecture de Franchetta forte

Sans résumé     

Ma?analytische Fluorbestimmung mittels Zirkon-Alizarin-Farblackes

Zusammenfassung Eine neue titrimetrische Art der Fluorbestimmung wurde beschrieben und eine allgemeine Arbeitsvorschrift gegeben.Die Methode ist für Fluor-Ionen jeder Art, sowohl für ionogen als auch für komplex gebundene, anwendbar und eignet sich vor allem als Betriebs-Schnellverfahren und für Reihenanalysen.     

The Arrow of Time in the Equations of Motion

It is argued that time's arrow is present in all equations of motion. But it is absent in the point particle approximations commonly made. In particular, the Lorentz-Abraham-Dirac equation is time-reversal invariant only because it approximates the charged particle by a point. But since classical electrodynamics is valid only for finite size particles, the equations of motion for particles of finite size must be considered. Those equations are indeed found to lack time-reversal invariance, thus ensuring an arrow of time. Similarly, more careful considerations of the equations of motion for gravitational interactions also show an arrow of time. The existence of arrows of time in quantum dynamics is also emphasized.